Corn, callus and wart removing pads

ABSTRACT

A wart, callus and/or corn removing pad including a layer of hydrocolloid adhesive material having a periphery and an underside, a medicated plaster secured centrally to the underside of the layer of hydrocolloid adhesive material and including salicylic acid therein, a barrier layer interposed between the medicated plaster and the layer of hydrocolloid adhesive material to prevent diffusion of the salicylic acid in the medicated plaster to the layer of hydrocolloid adhesive material, an outer layer secured to the layer of hydrocolloid material, the outer layer at least having a border extending outwardly of the layer of hydrocolloid adhesive material, the border having an underside, a layer of adhesive material on the underside of the border, a release liner releasably secured to the underside of the hydrocolloid adhesive layer, and a paper release tab releasably secured to an upper surface of at least one of the hydrocolloid adhesive layer and the outer layer at one side thereof.

BACKGROUND OF THE INVENTION

The present invention relates generally to pads for corns, calluses andwarts, and more particularly, to an improved corn, callus and wartremoving pad.

Corns are a painful type of hyperkeratosis, found principally overprominent toe joints and between toes. There are two common types ofcorns: Heloma Durum and Heloma Molle. Heloma Durum (hard corn) is ahyperkeratotic lesion which appears over a bony prominence and may havea deep nucleus. These corns are normally very tender and painful. TheHeloma Molle (soft corn) is a hyperkeratotic lesion which is foundbetween the toes. The soft corn results from pressure exerted betweenadjacent toes and is soft due to moisture between the toes.

A callus may be a diffuse or circumscribed area of hyperkeratosis at asite of repeated pressure and friction. In cases where there is aforefoot imbalance the plantar callus may be found where the metatarsalheads are most prominent.

Both common and plantar warts are simple papillomas caused by a virus.They may be sharply circumscribed with their edges clearly demarcatedfrom the surrounding skin. Their center is darker than the surroundingskin and they may have a mosine appearance. Plantar warts are found onthe plantar surface of the foot. They differ from calluses and are notnecessarily found over bony prominences. Common warts are typicallyfound on the fingers and hands. Warts are usually painful to squeezing.Plantar warts often exhibit pain from the pressure of walking.

Medicated pads are known for placement over corns, calluses and warts,and which contain an ingredient, such as 40% salicylic acid by weight ina rubber based vehicle, for removing corns, calluses and warts. Forexample, such pads are sold by Schering-Plough Healthcare Products, Inc.of Memphis, Tenn. under the house trademark “DR. SCHOLL'S”, and underthe particular trademarks “CLEAR AWAY” and “ONE STEP”.

Specifically, with such known pads, there is a relatively thick centercushion formed of ethylene foam or ethylene vinyl acetate (EVA),polyethylene or like material having a circular opening, and anelongated vinyl film secured to the upper surface of the center cushionsection and extending outwardly from opposite sides thereof. An adhesiveis applied to the lower surfaces of the entire thick center cushionsection and the elongated portions of the vinyl film that extendoutwardly from opposite sides of the thick center cushion section. Ineffect, the shape is similar to a conventional adhesive bandage, butwith adhesive material also provided on the lower surface of the centercushion.

A disk containing the salicylic acid is provided in the recess, and isseparated from the remainder of the center cushion and from the vinylstrip by a barrier layer. A release liner is provided on the undersideof the pad, and extends along the entire center cushion and vinyl film.Also, a paper release tab is releasably secured to the lower surface ofone free end of the vinyl strip.

In use, a person removes the release liner, thereby exposing theadhesive layer applied to the lower surfaces of the entire thick centercushion and the elongated portions of the vinyl film that extendoutwardly from opposite sides of the thick center cushion. The lowersurfaces of the entire thick center cushion and the elongated portionsof the vinyl film that extend outwardly from opposite sides of the thickcenter cushion are then secured to the person's skin, such that themedicated disk covers the corn, wart or callus to be removed. The paperrelease tab is then removed.

However, such product has a generally high profile, that is, arelatively large cross-sectional thickness. Also, this arrangementrequires adhesive to be applied to both the lower surfaces of the entirethick center cushion and the elongated portions of the vinyl film thatextend outwardly from opposite sides of the thick center cushion.

More importantly, the center cushion is water impermeable. When theperson perspires, moisture and liquid can form an interface layerbetween the medicated disk and the skin containing the corn, callus orwart. Also, such interface layer tends to weaken the adhesive, so thatthe pad tends to fall from the skin after a relatively short period oftime in the presence of such liquid interface layer.

A further problem with such product is that the salicylic acid tends toevaporate and be lost to the environment over time. For example, intests performed in accelerated aging conditions under a temperature of40/C and 75% relative humidity, over a three month period, for a productstarting with 42% salicylic acid by weight, only 36-37% salicylic acidby weight remained. This represents a very large loss of medicament.

It is known to provide bandages out of other materials. For example, itis known to provide trauma bandages made from a hydrocolloid adhesivelayer. However, these trauma bandages do not include any transdermaldevice containing any keratolytic agent (skin removing) or othermedicaments.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide amedicated pad that overcomes the problems with the aforementioned priorart.

It is another object of the present invention to provide a medicated padparticularly adapted for removing warts, calluses and corns.

It is still another-object of the present invention to provide amedicated pad which uses less adhesive than conventional medicated pads.

It is yet another object of the present invention to provide a medicatedpad in which the center hydrocolloid adhesive layer performs the dualfunction of an adhesive layer and a cushion.

It is a further object of the present invention to provide a medicatedpad in which adhesion is increased in the presence of a liquid.

It is a still further object of the present invention to provide amedicated pad which will adhere to a person's skin for a longer periodof time.

It is a yet further object of the present invention to provide amedicated pad in which less medicament will be lost to the environment.

It is another object of the present invention to provide a medicated padhaving a longer shelf life than conventional medicated pads.

In accordance with an aspect of the present invention, a medicated padincludes a center cushion layer having adhesive and liquid absorbingproperties, said center cushion layer having a periphery and anunderside, a medicated plaster secured to the underside of the centercushion layer, a barrier layer interposed between the medicated plasterand the center cushion layer to prevent diffusion of any medicament inthe medicated plaster to the center cushion layer, an outer layersecured to the center cushion layer, the outer layer at least having aborder extending outwardly of the layer of center cushion layer, theborder having an underside, and a layer of adhesive material on theunderside of the border. Preferably, the medicament includes salicylicacid, and the medicated plaster is secured at a substantially centralposition of the center cushion layer.

The barrier layer is made from a material selected from the groupconsisting of polyester film, polypropylene and polyolefin films.

A release liner is releasably secured to the underside of the centercushion layer. The release liner is made from a material selected fromthe group consisting of polyester film, polypropylene film, polyethylenefilm, polyolefin films, paper and polyethylene/paper laminates orfilm/paper laminates.

A release tab is releasably secured to an upper surface at one side ofat least one of the center cushion layer and the outer layer. Therelease tab is made from a paper material or polymer film.

The center cushion layer may also include a recess at the undersidethereof, and the barrier layer and the medicated plaster are positionedat least partially in the recess. In one embodiment, the recess includesa side wall and a bottom wall, the barrier layer is interposed betweenthe bottom wall and the medicated plaster, and the medicated plaster isspaced apart from the side wall of the recess. In another embodiment,the recess includes a side wall and a bottom wall, and the barrier layeris interposed between the side and bottom walls of the recess and themedicated plaster.

In accordance with another aspect of the present invention, a medicatedpad includes a layer of hydrocolloid adhesive material having aperiphery and an underside, a medicated plaster secured to the undersideof the layer of hydrocolloid adhesive material, a barrier layerinterposed between the medicated plaster and the layer of hydrocolloidadhesive material to prevent diffusion of any medicament in themedicated plaster to the layer of hydrocolloid adhesive material, anouter layer secured to the layer of hydrocolloid adhesive material, theouter layer at least having a border extending outwardly of the centercushion layer, the border having an underside, and a layer of adhesivematerial on the underside of the border.

In accordance with still another aspect of the present invention, amedicated pad includes a layer of hydrogel adhesive material having aperiphery and an underside, a medicated plaster secured to the undersideof the layer of hydrogel adhesive material, a barrier layer interposedbetween the medicated plaster and the layer of hydrogel adhesivematerial to prevent diffusion of any medicament in the medicated plasterto the layer of hydrogel adhesive material, an outer layer secured tothe layer of hydrogel adhesive material, the outer layer at least havinga border extending outwardly of the center cushion layer, the borderhaving an underside, and a layer of adhesive material on the undersideof the border.

The above and other features of the invention will become readilyapparent from the following detailed description thereof which is to beread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a medicated pad according to the presentinvention;

FIG. 2 is a bottom plan view of the medicated pad of FIG. 1;

FIG. 3 is a cross-sectional view of the medicated pad of FIG. 1, takenalong line 3—3 thereof;

FIG. 4 is a cross-sectional view similar to FIG. 3 of a medicated padaccording to a second embodiment of the present invention; and

FIG. 5 is a cross-sectiona. view similar to FIG. 3 of a medicated padaccording to a third embodiment of the present invention.

DETAILED DESCRIPTION

Referring to the drawings in detail, and initially to FIGS. 1-3, a pad10 according to a first embodiment of the present invention for removingcorns, calluses and warts, includes a center cushion layer 12 of amaterial having adhesive and liquid absorbing qualities. In this regard,a preferred material of layer 12 is a hydrocolloid adhesive materialhaving a preferred thickness in the range of 0.001 inch (1 mil) to 0.050inch (50 mils), with a most preferred thickness of 0.018 inch (18 mils).A suitable hydrocolloid adhesive material is sold by Avery DennisonCorp. of Painesville, Ohio under the designation #2190H. An alternativematerial is a hydrogel adhesive having a preferred thickness in therange of 0.001 inch (1 mil) to 0.050 inch (50 mils), with a mostpreferred thickness of 0.020 inch (20 mils). Hydrogels are water-basedpolymeric matrices with a gel-like consistency. Hereinafter, this layer,for ease of explanation, will be referred to as a hydrocolloid adhesivelayer.

Preferably, when used as a corn remover, layer 12 has the shape of arhombus with a greatest length of about 1.375 inches and a greatestwidth of about 0.50 inch. Hydrocolloids are elastomeric plasters inwhich colloidal water absorbable particles are suspended. However,hydrocolloid adhesive layer 12 will have different configurations anddimensions depending upon the particular application, and the specificshape and dimensions are not relevant to the present invention.

Hydrocolloid adhesive layer 12 has properties that are moderatelyadhesive, and when heated, provides greater adhesive properties. Thus,when placed on a person's skin, hydrocolloid adhesive layer 12 willstick to the person's skin, and as the person's body temperature heatsup hydrocolloid adhesive layer 12, the adhesive activity of hydrocolloidadhesive layer will increase. This means that there is no need toprovide a separate adhesive layer on the underside of hydrocolloidadhesive layer 12. Therefore, hydrocolloid adhesive layer 12 performsthe dual function of a cushioning layer and an adhesive layer.

It will be appreciated that hydrocolloid adhesive layer 12 is waterabsorbent. This means that, as a person perspires, the moisture andwater are absorbed by hydrocolloid adhesive layer 12. As a result, as aperson perspires, there is no liquid interface layer formed betweenhydrocolloid adhesive layer 12 and the person's skin. This means thatthere is no deterioration of the adhesive quality of hydrocolloidadhesive layer 12 in the presence of moisture and/or water, so that thepresent invention will stay on a person's skin for a longer period oftime. In fact, the absorption of water actually increases the adhesionof hydrocolloid adhesive layer 12 co the person's skin. Specifically, inthe presence of water, hydrocolloid adhesive layer 12 forms a hydrogellayer which is an adhesive that increases the adhesive quality ofhydrocolloid adhesive layer 12.

However, in order to provide an initial good adhesive quality prior tohydrocolloid adhesive layer 12 being heated, an outer layer 14 issecured to the upper surface of hydrocolloid adhesive layer 12. Outerlayer 14 can have a substantially hollow rhombus shape, but preferably,has a solid rhombus shape which merely overlays on top of hydrocolloidadhesive layer 12. In any event, when used as a corn remover, the outerperiphery of outer layer 14 forms a border 14 a which preferably has asubstantially rhombus shape which is the same as that of hydrocolloidadhesive layer 12, but of greater dimensions. For example, the rhombusof outer layer 14 can have a greatest length of about 1.625 inches and agreatest width of about 0.75 inch. However, outer layer 14 is notlimited by this configuration or dimensions. Outer layer 14 can be madefrom any suitable material, including but not limited to polyvinylchloride (PVC), polyurethane, polyethylene and polyolefin, and has apreferred thickness in the range of 0.0005 inch (0.5 mil) to 0.010 inch(10 mils), but is preferably made from a clear polyurethane film, soldby 3M Inc. of Minneapolis, Minn. under the designation #MSX 5527, with amost preferred thickness of 0.002 inch (2 mils).

Border 14 a of outer layer 14 has its lower surface coated with anadhesive layer 16. Thus, when pad 10 is initially placed on a person'sskin, adhesive layer 16 will hold pad 10 securely thereon. Subsequently,hydrocolloid adhesive layer 12 will heat up, thereby increasing theadhesive characteristics thereof, and further securely and releasablyholding pad 10 in such position.

It will be appreciated that pad 10 according to the present inventionuses one less coat of adhesive than the prior art “ONE STEP” pad sincehydrocolloid adhesive layer 12 has an adhesive quality itself.

Because of hydrocolloid adhesive layer 12, pad 10 stays adhered to aperson's skin longer than the aforementioned “ONE STEP” pad.

Because of the adhesive quality of hydrocolloid adhesive layer 12, whenshipped by manufacturers of the same, a top layer 15 is generallyapplied thereto, for example, a polyester film, polyethylene film,polyurethane or the like with a range of thickness between 0.0001 inch(0.1 mil) and 0.010 inch (10 mils). Preferably, such top layer 15 is aclear polypropylene film having a thickness of 0.00075 inch (0.75 mils).

In order to provide a beneficial keratolytic (skin removing) agent, forexample, 40% salicylic acid by weight, a medicated plaster 18 isprovided. Specifically, medicated plaster 18 is preferably made of asynthetic or natural rubber based matrix with 40% salicylic acid byweight. In such case, as is well known, the salicylic acid is mixed witha rubber mixture, a plasticizer and a tackifier, to form stiff rubbermedicated plaster 18. Although a disk shape is shown, the presentinvention is not limited thereby, and medicated plaster 18 can have anyshape. Medicated plaster 18 preferably has a thickness in the range of0.010 inch (10 mils) to 0.050 inch (50 mils), with a most preferredthickness of in he range of 0.020 inch (20 mils) to 0.025 inch (25mils).

Medicated plaster 18 is secured to the underside of hydrocolloidadhesive layer 12, preferably at a center position thereof. In thismanner, medicated plaster 18 is placed directly or the skin portioncorresponding to the wart, corn or callus, and is surrounded byhydrocolloid adhesive layer 12.

In order to prevent migration of the salicylic acid into hydrocolloidadhesive layer 12, which would occur if medicated plaster 18 weredirectly in contact with hydrocolloid adhesive layer 12, a barrier layer20 is connected between hydrocolloid adhesive layer 12 and medicatedplaster 18. Barrier layer 20 prevents migration of the salicylic acidfrom medicated plaster 18 to hydrocolloid adhesive layer 12. Barrierlayer 20 can be made from any suitable material including, but notlimited to, a polyester film, polypropylene and polyolefin films.Preferably, barrier layer 20 has a thickness in the range of 0.00025inch (0.25 mil) to 0.002 inch (2 mils), and is most preferably a clearpolyester film sold by Scapa Tapes Inc. of Windsor, Conn. underdesignation number RX529PX, with a thickness of 0.00005 inch (0.5 mil).

It has also been determined that there is less evaporation and loss tothe environment of the salicylic acid with pad 10 than with theaforementioned “ONE STEP” pad. Specifically, in three month tests inaccelerated aging conditions under a temperature of 40/C and 75%relative humidity, with medicated plaster 18 having 42% salicylic acidby weight, there was a loss of less than one percent (1%). With the samestarting tests with the aforementioned “ONE STEP” pad, the amount ofsalicylic acid dropped from 42% by weight to between 36% and 37% byweight. This result is surprising since hydrocolloid adhesive layer 12is water absorbent, and it would be expected that the salicylic acidwould be absorbed after evaporation into hydrocolloid adhesive layer.However, the direct opposite occurred, and pad 10 remained more stableover time than the aforementioned “ONE STEP” pad, that is, with lessloss of the salicylic acid.

In addition, a release liner 22 is releasably secured to theunderside-of pad 10, and particularly, in covering relation to theunderside or lower surfaces of hydrocolloid adhesive layer 12, outerlayer 14 with adhesive layer 16 thereon, and medicated plaster 18.Release liner 22 serves as a protective layer until pad 10 is to beused. Although release liner 22 is shown in a rectangular configuration,the present invention is not limited by this shape. Release liner 22 ispreferably transparent and can be made from any suitable materialincluding, but not limited to polyester film, polypropylene film,polyethylene film and polyolefin films, with a preferred range ofthickness from 0.002 inch (2 mils) to 0.010 inch (10 mils), and a mostpreferred thickness of 0.005 inch (5 mils). Alternatively, release liner22 can be made from a heavy weight paper, polyethylene/paper laminatesor film/paper laminates, with a preferred weight range of 30 to 150pounds per ream, and with a preferred weight of 90 pounds per ream. Thepreferred material, however, for release liner 22 is a silicone coatedpolyester film sold by Daubert Coated Products Inc. of Dixon, Ill. underthe designation 4020 HS and having a thickness of 0.005 inch (5 mils).

Lastly, pad 10 includes a paper release tab 24 releasably secured to theupper surface of hydrocolloid adhesive layer 12 and/or outer layer 14 atone side thereof. For a corn remover, paper release tab 24 preferablyhas a trapezoidal section 24 a that is releasably secured by theadhesive quality of hydrocolloid adhesive layer 12 on the upper surfaceof the same, and a substantially rectangular section 24 b that extendsout from hydrocolloid adhesive layer 12 and merely overlies releaseliner 22. Paper release tab 24 can be made from any suitable stock papersuch as that sold by Simpson Paper Company of Anderson, Calif. under thedesignation 100#C1s Litho Facer, and preferably has a weight in therange of 30 to 150 pounds per ream, with a most preferred weight of 100pounds per ream. Alternatively, release tab 24 can be made from apolymer film.

Although FIGS. 1 and 2 show the different elements in substantially thecorrect shapes and dimensions of the preferred embodiment for a cornremover, the thicknesses of the layers in FIG. 4 are not shown in thecorrect dimensions in order to better illustrate the present invention.

In use, a person pulls up on substantially rectangular section 24 b ofrelease tab 24 with one hand, while holding the portion of release liner22 immediately below with the other hand. This functions to remove pad10 from release liner 22. Pad 10 is then placed on the person's skin,with medicated plaster 18 immediately above the corn, callus or wart tobe removed. Adhesive layer 16 functions to secure pad 10 thereon. As theskin heats up, the adhesive quality of hydrocolloid adhesive layer 12increases, further adding to the securement of pad 10 to the person'sskin. Paper release tab 24 is then pulled up. At this time, paperrelease tab 24 is detached from pad 10, leaving pad 10 on the person'sskin.

It will therefore be appreciated that pad 10 uses less adhesive thanconventional medicated pads, that is, with only a small adhesive layer16 at the outer periphery thereof. This is because hydrocolloid adhesivelayer 12 performs the dual function of an adhesive layer and a cushion.Also, in the presence of a liquid and/or moisture, hydrocolloid adhesivelayer 12 absorbs the same, with the result that the adhesive qualitiesare increased. This means that pad 10 will adhere to a person's skin fora longer period of time than conventional medicated pads.

Another advantage with the present invention is that less medicamentwill be lost to the environment. This is due to the combination ofhydrocolloid adhesive layer 12 with medicated plaster 16. As a result,pad will have a longer shelf life than conventional medicated pads.

It will be appreciated that various changes and modifications within thescope of the present invention can be provided. For example, theunderside of hydrocolloid adhesive layer 12 can be provided with arecess 26 at the center thereof, and barrier layer 20 and medicatedplaster 18 can be provided in recess 26 in spaced relation to the sidewalls of recess 26, as shown in FIG. 5. In such case, a portion ofmedicated plaster 18 extends out from recess 26 to a lower height thanthe lower surface of hydrocolloid adhesive layer 12.

Alternatively, barrier layer 20 can additionally include a side wall 20a itself between the side walls of recess 26 and the outer peripheralside of medicated plaster 18, as shown in FIG. 6.

Although the present invention has been discussed in relation to a padfor removing warts, corns and calluses and containing salicylic acid asthe keratolytic agent, the present Invention can be used with any otherkeratolytic agent and/or medicament, such as an antibiotic agent,antimicrobial agent, antifungal agent or the like.

Having described specific preferred embodiments of the invention withreference to the accompanying drawings, it will be appreciated that thepresent invention is not limited to those precise embodiments and thatvarious changes and modifications can be effected therein by one ofordinary skill in the art without departing from the scope or spirit ofthe invention as defined by the appended claims.

Parts designator

10 pad

12 hydrocolloid adhesive layer

14 outer layer

14 a border

15 top layer

16 adhesive layer

18 medicated plaster

20 barrier layer

20 a side wall

22 release liner

24 paper release tab

24 a trapezoidal section

24 b rectangular section

26 recess

What is claimed is:
 1. A medicated pad comprising: a center cushionlayer having adhesive and liquid absorbing properties, said centercushion layer having a periphery and an underside, wherein the centralcushion layer is formed from a hydrocolloid that is a natural orsynthetic rubber co-mingled with a cellulosic or hygroscopic material,or wherein the central cushion layer is formed from a hygroscopichydrocolloid co-mingled with a solid matrix of rubber, a medicatedplaster secured to the underside of said center cushion layer, whereinthe adherence of the hydrocolloid surrounding the medicated plasterincreases when the central cushion layer absorbs moisture and when it isheated to topical body temperatures, a barrier layer interposed betweensaid medicated plaster and said center cushion layer to preventdiffusion of any medicament in said medicated plaster to said centercushion layer, an outer layer secured to said center cushion layer, saidouter layer at least having a border extending outwardly of said centercushion layer, said border having an underside, and a layer of adhesivematerial on the underside of said border.
 2. A medicated pad accordingto claim 1, wherein said medicament includes salicylic acid.
 3. Amedicated pad according to claim 1, wherein said medicated plaster issecured at a substantially central position of said center cushionlayer.
 4. A medicated pad according to claim 1, wherein said barrierlayer is made from a material selected from the group consisting ofpolyester film, polypropylene and polyolefin films.
 5. A medicated padaccording to claim 1, further comprising a release liner releasablysecured to the underside of said center cushion layer.
 6. A medicatedpad according to claim 5, wherein said release liner is made from amaterial selected from the group consisting of polyester film,polypropylene film, polyethylene film, polyolefin films, paper andpolyethylene/paper laminates or film/paper laminates.
 7. A medicated padaccording to claim 1, further comprising a release tab releasablysecured to an upper surface at one side of at least one of said centercushion layer and said outer layer.
 8. A medicated pad according toclaim 7, wherein said release tab is made from a material selected fromthe group of a paper material and a polymer film.
 9. A medicated padaccording to claim 1, wherein said center cushion layer includes arecess at the underside thereof, and said barrier layer and saidmedicated plaster are positioned at least partially in said recess. 10.A medicated pad according to claim 9, wherein said recess includes aside wall and a bottom wall, said barrier layer is interposed betweensaid bottom wall and said medicated plaster, and said medicated plasteris spaced apart from said side wall of said recess.
 11. A medicated padaccording to claim 9, wherein said recess includes a side wall and abottom wall, and said barrier layer is interposed between said side andbottom walls of said recess and said medicated plaster.
 12. A medicatedpad comprising: a layer of hydrocolloid adhesive material having aperiphery and an underside, wherein the hydrocolloid layer is formedfrom a hydrocolloid that is a natural or synthetic rubber co-mingledwith a cellulosic or hygroscopic material, a medicated plaster securedto the underside of said layer of hydrocolloid adhesive material,wherein the adherence of the hydrocolloid layer surrounding themedicated plaster increases when the hydrocolloid layer absorbs moistureand when it is heated to topical body temperatures, a barrier layerinterposed between said medicated plaster and said layer of hydrocolloidadhesive material to prevent diffusion of any medicament in saidmedicated plaster to said layer of hydrocolloid adhesive material, anouter layer secured to said layer of hydrocolloid adhesive material,said outer layer at least having a border extending outwardly of saidcenter cushion layer, said border having an underside, and a layer ofadhesive material on the underside of said border.
 13. A medicated padaccording to claim 12, wherein said medicament includes salicylic acid.14. A medicated pad according to claim 12, wherein said medicatedplaster is secured at a substantially central position of said layer ofhydrocolloid adhesive material.
 15. A medicated pad according to claim12, further comprising a release liner releasably secured to theunderside of said layer of hydrocolloid adhesive material.
 16. Amedicated pad according to claim 12, further comprising a release tabreleasably secured to an upper surface at one side of at least one ofsaid layer of hydrocolloid adhesive material and said outer layer.
 17. Amedicated pad according to claim 12, wherein said layer of hydrocolloidadhesive material includes a recess at the underside thereof, and saidbarrier layer and said medicated plaster are positioned at leastpartially in said recess.
 18. A medicated pad according to claim 17,wherein said recess includes a side wall and a bottom wall, said barrierlayer is interposed between said bottom wall and said medicated plaster,and said medicated plaster is spaced apart from said side wall of saidrecess.
 19. A medicated pad according to claim 17, wherein said recessincludes a side wall and a bottom wall, and said barrier layer isinterposed between said side and bottom walls of said recess and saidmedicated plaster.
 20. A medicated pad comprising: a layer of hydrogeladhesive material having a periphery and an underside, wherein thehydrogel layer is formed from a hygroscopic hydrocolloid co-mingled witha solid matrix of rubber, a medicated plaster secured to the undersideof said layer of hydrogel adhesive material, wherein the adherence ofthe hydrogel layer surrounding the medicated plaster increases when thehydrogel layer absorbs moisture and when it is heated to topical bodytemperatures, a barrier layer interposed between said medicated plasterand said layer of hydrogen adhesive material to prevent diffusion of anymedicament in said medicated plaster to said layer of hydrogel adhesivematerial, an outer layer secured to said layer of hydrogel adhesivematerial, said outer layer at least having a border extending outwardlyof said center cushion layer, said border having an underside, and alayer of adhesive material on the underside of said border.
 21. Amedicated pad according to claim 20, wherein said medicament includessalicylic acid.
 22. A medicated pad according to claim 20, wherein saidmedicated plaster is secured at a substantially central position of saidlayer of hydrogel adhesive material.
 23. A medicated pad according toclaim 20, further comprising a release liner releasably secured to theunderside of said layer of hydrogel adhesive material.
 24. A medicatedpad according to claim 20, further comprising a release tab releasablysecured to an upper surface at one side of at least one of said layer ofhydrogel adhesive material and said outer layer.
 25. A medicated padaccording to claim 20, wherein said layer of hydrogel adhesive materialincludes a recess at the underside thereof, and said barrier layer andsaid medicated plaster are positioned at least partially in said recess.26. A medicated pad according to claim 25, wherein said recess includesa side wall and a bottom wall, said barrier layer is interposed betweensaid bottom wall and said medicated plaster, and said medicated plasteris spaced apart from said side wall of said recess.
 27. A medicated padaccording to claim 20, wherein said recess includes a side wall and abottom wall, and said barrier layer is interposed between said side andbottom walls of said recess and said medicated plaster.